Filippo Luigi Gilii

(1756-1821) Filippo Luigi Gilii was an Italian naturalist, clergyman, and Director of the Vatican Observatory from 1800-1821. For 21 years Gilii made twice daily meteorological readings at the Observatory, and it was Gilii who established the meridian line in front of St. Peter's Basilica, using shadows to determine the length of seasons. His astronomical knowledge so impressed Spanish botanists Ruiz and Pavon that they named the genus Gilia for him.